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They are usually dark in color, owing to the abundance of ferro-magnesian silicates, of high specific gravity and liable to decomposition. For these reasons they have been defined as a melanocrate series (rich in the dark minerals ); and they are often accompanied by a complementary leucocrate series (rich in the white minerals feldspar and ...
The Symplocos genus of plants, which grows in semi-tropical regions, also bioaccumulates aluminum, and is still popular with natural dyers. Using natural dyes to color the yarn of Tasar silk. Across Asia and Africa and the Americas, patterned fabrics were produced using resist dyeing techniques to control the absorption of color in piece-dyed ...
Vivianite is a secondary mineral found in a number of geologic environments: the oxidation zone of metal ore deposits, in granite pegmatites containing phosphate minerals, in clays and glauconitic sediments, and in recent alluvial deposits replacing organic material such as peat, lignite, bog iron ores and forest soils (all).
Dark-skinned people, who produce more skin-protecting eumelanin, have a greater protection against sunburn and the development of melanoma, a potentially deadly form of skin cancer, as well as other health problems related to exposure to strong solar radiation, including the photodegradation of certain vitamins such as riboflavins, carotenoids ...
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In mineralogy, an inclusion is any material trapped inside a mineral during its formation. In gemology , it is an object enclosed within a gemstone or reaching its surface from the interior. [ 1 ] According to James Hutton 's law of inclusions, fragments included in a host rock are older than the host rock itself.
Enriched levels of potash have K 2 O grades between 8 and 12%, thickness up to 50 metres (160 ft) and are associated to the glauconitic levels, dark-green in color. Glauconite is authigenic and highly mature. The high concentration of this mineral is related to a depositional environment with a low sedimentation rate.
Data source: Fiserv. Fiscal years end Dec. 31. This steady growth underscores the popularity of its service offerings and also demonstrates superb operating leverage as the business's net income ...